. >> it declared that all slaves in states rebelling against the union were to be forever free but didn't immediately end slavery. lincoln didn't have the power to enforce it in areas under confederate control. what the document did do was become a symbol of hope for nearly four million slaves and fundamentally changed the character of the war. >> it was important. it was a military measure. lincoln did not do this for humanitarian regions. reasons. he did it as a consequence of being commander-in-chief. >> this is the official document with the u.s. seal and lincoln's signature, setting it party from other copies and drafts. it's rarely been made accessible. having been badly damaged decades ago by light exposure. conservators rotate which pages are shown. >> our strategy is to limit the amount of light exposure and that means to limit the length of time it's on display and keep light levels low. >> preserving this piece of history for people today and generations to come. >> the emancipation proclamation will be on display in the rotunda of the national archives today, monday and tuesda